A staple gun or powered stapler is a hand-held machine used to drive heavy metal staples into wood or masonry. Staple guns are used for many different applications and to affix a variety of materials, including insulation, house wrap, roofing, wiring, carpeting, upholstery, and hobby and craft materials. A rivet tool, or rivet gun, is a type of tool used to drive rivets. Rivet guns vary in size and shape and have a variety of handles and grips.